Go 错误处理

// errmsg.go
package main

import (
	"errors"
	"fmt"
)

type DivideError struct {
	dividee int
	divider int
}

func (de *DivideError) Error() string {
	strFormat := `
		Cannot proceed, the divider is zero.
		dividee: %d
		divider: %d
	`
	return fmt.Sprintf(strFormat, de.dividee, de.divider)
}

func PrintErrTest() error {
	return errors.New("error!!!!")
}

func Divide(varDividee int, varDivider int) (result int, errormsg string) {
	if varDivider == 0 {
		dData := DivideError{
			dividee: varDividee,
			divider: varDivider,
		}
		errormsg = dData.Error()
		return
	} else {
		return varDividee / varDivider, ""
	}
}

func main() {
	//  1
	error := PrintErrTest()
	if error != nil {
		fmt.Println(error)
	}

	// 2
	if result, errorMsg := Divide(100, 10); errorMsg == "" {
		fmt.Println("100/10 =", result)
	}

	if _, errorMsg := Divide(100, 0); errorMsg != "" {
		fmt.Println("errorMsg is :", errorMsg)
	}
}

输出：

error!!!!
100/10 = 10
errorMsg is : 
		Cannot proceed, the divider is zero.
		dividee: 100
		divider: 0